A wind farm or a wind park may comprise one or more wind turbines which convert mechanical energy contained in wind to electrical energy. The wind turbines may be connected to a point of common coupling (PCC) at which point or node a number of electrical conditions or properties must be satisfied. In particular, the electrical properties reactive power Q, voltage V and power factor cos(φ) at the point of common coupling may satisfy particular requirements.
EP 2 108 828 A2 discloses a wind farm collector system loss optimization, wherein a collector system includes a plurality of transformers connected to each wind turbine generator and a substation transformer connecting the wind farm collector system to the electrical grid. A control function may include voltage and real and reactive power commands to the individual wind turbine generators, wherein an algorithm has a technical effect to minimize electrical losses for the wind farm system.
There may be a need for a controller, in particular a controller for controlling a park transformer, for a wind park, and for a control method for controlling a park transformer, wherein an efficiency of energy production and/or supply to the utility grid is improved and wherein at the same time desired or required electrical conditions are satisfied at a point of common coupling, where the wind turbines are connected.